I doubt that we can achieve absolute objectivity, that's why I wrote that I consider it fairly objective, not that it is. That said I don't see a reason why should Columbia Journalism Review or Poynter Institute be any better arbiters of what is correct way to measure bias. (Especially because both are competition.)
Also Poynter Institute has record of "weaknesses in the methodology".[1]
> The Columbia Journalism Review describes Media Bias/Fact Check as an amateur attempt at categorizing media bias and Van Zandt as an "armchair media analyst."[3] The Poynter Institute notes, "Media Bias/Fact Check is a widely cited source for news stories and even studies about misinformation, despite the fact that its method is in no way scientific."[4]